Thanks to Samluke and others for the ideas and the display. I came up with a more or less permanent installation for a knock counter and blink code indicator. It requires drilling a few holes and a slot in the glove box but other than that is totally reversable. You have to open the glove box to see it or use it.

When I was using the temporary set up in the other thread I was not getting any counts.

On the way back from Wallace Idaho I started getting a dozen or so counts per full throttle & boost run. I think I got some low grade gas. When the tank went to half full I filled it again with 91 octane. I still got some counts but only two or three. I put some octane booster in and got one count running up though second and part of third up a hill, I got one count. Once this tank is low I will try again with all new gas.

I know knock and pinging/pinking is not the same but they're pretty closely related. The noise you can hear when you've got some poor octane fuel, under load up a hill or overboosting. Does this get counted?

You can rid yourself of those pesky low load counts by using a Hobbs switch so it only counts while under higher boost.

You just tap into the power circuit and then install a power switch to read out while sitting still if wanted.

Fortunately, I have found that once using e85 full time , the counts are so minimal that the counter is not as necessary unless running on the edge of lean. If I were using reg fuel this item would be invaluable

Thanks Sid. I'll likely try the 10PSI switch with the NO option. (now understand the NO vs. NC choice!)

Final question - where in the boost track would you attach the switch? I'm thinking the most likely place would be somewhere off the intake manifold. Before drilling holes, maybe I could T it into one of the major pressure lines off the manifold?